Controlling apparatus for pneumatic-dispatch systems



Feb. 1, 1927.

J. T. COWLEY CONTROLLING APPARATUS 'FOR PNEUMATIC DISPATCH SYSTEMS4Original Filed July l2, 1923 Patented Feb. 1, 1927,.

JAMES T. COWLEY, @E SYBAGUSE, YORK, ASSTGNGF; EJE T Ol? SYRACUSE, NE'WA. CDRPORA CONTROLLIHG APPARATUS FR PrlEUltAlC-DSATCH SYSTEMS.

original appueanon inea muy is, ieee,

Serial No. 651,065, Patent 11o. 1586.249, dated .Tune 1, 1926.

Divided and this application filed December 5, 153/25. Serial No.73,357.

This invention pertains to powerI control apparatus for pneumaticdispatch systems and more particularly to automatic apparatus of the`general type disclosed in the patent to Libby 968,576; dated august 3G,1910, wherein the opening and closing` or a main valve is determined byfluid motor means actuated by pressure variations in the transmissionline` the pre-sent application beinn a division ot my application SerialNo. 651,065 ttor controlling` apparatus for pneumatic dispatch systems,tiled July 12, 1923, and patented lune 1, 192%.llumber 1586.219.

rlhe principal objects of the present invention are to provide improvedcontrolling' apparatus of the above type which is sensitively responsiveto slight pressure variations in the transmission tube incident to theintroduction of a carrier therein or its delivery therefrom, to providean arrangement such that the slight movement of a pneumatic,` torexample a 'flexible diaphragm eX- posed to transmission tube pressurewhich occurs when a carrier is introduced into the transmission tube.will initiate the full opening; movement ot the main valve; to providemeans independent ot the aforesaid pneumatic responsive to slight dropin pressure in the transmission line `tor initiating the closing' ot themain valve; to provide for the rapid restoration of parts to normalposition after the discharge oit the'last carrier from the transinissiontube; and in general to provide an apparatus ot simple and reliablecharacter having' few moving' parts and which occupies al minimum otspace.

.ln the aceompanyin n` drawings one desir'- able embodinient of theinvention is disclosed by way oit example, and in such drawings.

Fig. 1 is a fragmentary vertical section to enlarged scale, such sectionheine` taken on the center line o1 the main valve and showing the partsin their normal position, the main valve being; closed; and

Fig'. 2 is a diagrammatic view illustrating a preferred arrangement ofelectrical circuits employed in the operation ot the controllinovapparatus. Y

lic'tei to the drawings the numeral 1 indicates the main outer casing`ot the apparat-us such casing; beine hollow and providiupr the chamber 2wl'iich is connected in usual manner by means oit a suitable pipe,

not shown, to the suction drum or exhauster ot the dispatch system.

Within the casing;` 1 an inner casing` 3 'Inrnishes an inner chamber el,which communicates by means of a passage with the transmission tube7 notshown.

The upper and lower walls of the inner casing 3 are provided withaligned valve apertures which are norn'lally closed bythe spaced heads 7and 8 oit a ba anced main valve 6. A smallk passage 9, here siiown asformed in the head S of the main valve, provides for the movement of asmall quantity of air commonly reterred to as the minimum flow, from thechamber l tok theV outer chamber 1. rihe valve 6 is furnished with astem 10 suitably `guided in an openingr in the upper wall 11 ot theouter housing or casing 1.

The wall 11 is furnished with an outstanding); tlann'e portionproviding' a seat for 'the edges oit a lflexible diaphragm 12 which isclamped to the seat by a cover member 13,k The diaphragm 12 separatesthe space between 4the cover 13 and the wall 11 into upper and lowerchambers 141 and 15 respectively. The chamber 1 communicates with thechamber 1l by means of a passage 16 which opens through the diaphragm 12at the point 18.

The central part of the diaphragi'ni12`r is clamped between plates 20and 21 which are secured to the stem 10 by means of a nut 22. A rod 23,forming an extension ot the stem of thevalve 6, is provided with a nut24k at its lower end and bears against the nut 22 on the upper end ofthe stem 10. li desired the extension 23 may torm an integralcontinuation of the stem 10. A passage 1GaM extends axially along thestem 10 and its continuation 23 and opens laterally with chamber 141 andat its lower end is provided with a` lateral branch 15a open-inn' at theouter surface of the stem but norm ally closed by the wall member 11.

A coil spring` encircles the rod 223 and bears at one end airainsiv thenut 211. The upper end of the rod 23 passes throughv a guide opening ina gland 26 having' threaded engagement with a suitable opening in thecover 13 and the upper end of the spring` 25 bears against the innersurface of this gland.

The cover 13 supports an auxiliary pneumatic motor comprising` anupstanding an- Crt) nular flange 27, here shown as integral with thecover 18, and a cover member 28 suitably secured to the flange 27 andwhich clamps the edges of a diaphragm 3l against the upper edge of theflange 27. This diaphragm 31 separates the space between the covermember 2S and the member 13 into upper and lower chambers 29 and 30respectively. The lower chamber 30 is provided with a small port 32leading to the outer atmosphere while the upper chamber 29 is connectedby means of a pipe 33 to the transmission line so that transmission linepressure is always maintained in the chamber 29. The diaphragm 31 isprovided with a stem 34 which is guided to slide in a gland 36 and whichis held in normal position by means of a spring1 35 encircling the stemand bearing against the inner surface ot' the gland.

The cover 13 of the main motor is furnished with an upstanding boss 37provided with a guide bore 38 parallel to the stein 10 of the valve andwhich receives a sliding bar or rod 89. A spring` 40 bears against thesurface of the bar or rod 30 and tends frictionally to retain the latterin whatever position it may be placed. This rod 39 is furnished withaxially spaced stops for example, the upper and lower ends of elongateslot 4l in its outer surface. and is provided at its upper end with ataper cani finger or plug 42. This plug and preferably the entire bar 89is made of some suitable insulating material.

The upper end of the post or stem eXtension 23 is provided with abracket 44, one end of which is disposed within the slot or recess 41 inthe rod 39. The bracket 44 is also furnished with an upstanding part 45to which a cam bar 46 is secured.

The cam bar 46 is furnished with an inclined cam surface 46a at itsupper end.

The main housing 1 is provided with a lateral extending' hollow boss 47providinga cavity 48 which communicates freely with the chamber 15. Thiscavity 48 communicates with the outer atmosphere through a port definedby an annular valve seat with which a valve 49 cooperates. This valve isnormally7 closed and is furnished with a stem 50 constituting orconnected to the core of a solenoid 51.

One terminal of the solenoid windings is connected by a wire 52 to onepole of a battery 53 or other sui-table source of electrical energy. Theother pole of this battery is connected by wires 54 and 54n with aresilient arm 55 suitably mounted upon an insulating block 55a'. Thefree extremity of this resilient arm is arranged immediately above theupper end of the stem 84 of the diaphragm 31 and is furnished with anelectrical contact element 56. A cooperating' contact element 57 iscarried by a iiexible arm 58 parallel to the arm 55 and also mountedupon the block 55a. The arm 5S is connected by a wire 59 to a wire60.1unning to the other terminal of the solenoid windings.

The wire 60 is also connected by means of a wire to a resilient arm 6lsuitably supported at one end upon aninsulating support and furnished atits other end with the contact member 63. This contact member normallyengages a cooperating contact member 64- carried at the lower end of asecond resilient arm 62 which in turn is supported at its upper end uponan insulating support. The lower ends of the arms 61 and 62 diverge fromeach other and are disposed in'nnediately above the upper end of the cammember 42 in such a way that upward movement of the post or bar 39causes the cam 42 to enter between the contacts 63 and 64 and toseparate the latter.

The resilient supporting arm 62 is connected by a wire 66 to anotherresilient arm 67 supported upon an insulating block 67a. The lower endof the arm 67 carries an electrical contact 68 and the arm 67 isprovided at a point intermediate its length with a cam follower block08a having an inclined cani surface engageable with the cam surface476FL of the cani bar 46. The contact 68 cooperates with an opposedcontact GT carried by a resilient arm 'TO also mounted upon the block67a. This arm 70 is connected by a wire 71 to the wire 54.

i The lower wall of the chamber 15 of the main motor is furnished with asmall port 8O leading to the outer atmosphere. l valve 81 is adapted toclose this port. This valve 81 is carried by a lever 82 pivotallysupported at 83 and provided with a counterweight 84 which tends toswing the lever so as to close the valve 9,1 against the port 80. A rodS5 preferably secined to the lower plate 2l passes through the port S6and contacts with the valve 81. normally holdingthe valve open inopposition to the weight 84. lllanifestly the rod 85 might alternativelybe secured to the valve or might be independent of both the valve andplate and suitably guided for transmitting movement from the plate tothe valve.

In the arrangement thus provided the electrical: circuit through thesolenoid 51 comprises two loopsthe wires 54. 7L 67. 66, 65. 60 and 52constituting one loop7 and the wires 54, 54, 59 60 and ionstit-utingithe other loop. The contacts 63 and 64 form a normally closed switch inthe first named loop of the circuitand the contacts 66 and 69 constitutea normally open switch in the same loop. The contacts 56 and 5T form anormally open switch in the other loop of the circuit.

The operation of the device is substantially as follows: Vit beingunderstood that lll? remesa the parts normally occupy substantially thepositions shown in Fig. 1 when no carrier is in the transmission tube..their a carrier is introduced into.- the tube the pressure in the latterdrops slightly below normal due tothe cutting ott ot the minimum tloiv,whereupon. the diaphragm 12 immediately 'liexes upwardly to a slightextent but not sutlicient to open the main valve 6. This slight movementis enough to cause the cam member 46 to press resilient arm GT to theleft as viewed in Fig. 1 so as to bring' the contact 68 into engagementWith the contact 69.

rThe circuit is thus closed through the first loop as above described,thus energizing` the solenoid and thereby lifting the. valve t9 to admitatmospheric. pressurel to the cha-mber 15. This permits thel diaphragm`12 to rise freely to its full extent. thu-s opening the main valve 6and connecting the suction drum with the transmission tube. This causesa marked decrease in pressure in; the transmission tube resulting'- in arapid tloiv ot' air sutlicient to move the carrier toivard its.destination. This relatively large decrease in pressure in thetransmission tube is transmitted througlfi the pipe to the chamber 29ot' the auxiliary motor and thus raises the diaphragm 31. It may bestated at this point that the spring` 35. is sutliciently strong toprevent upward movement of the diaphragm 31 except when the main valveis at least partially open and a carrier is in the tube As the diaphragm3.1 rises it brings the contacts 56 and 5T into engagement. thusclosingI the circuit through the second loop comprisingl the Wires 59and 54a.. This action takes place jlust prior to the full. opening otthe main valve. As the main valve approaches its fully open position thearm 4:4 comes into engagement with. the, upper end of the recess 'stl inthe rod 39 and moves the latte-r up su'lticiently to insert the cammember t2 between the contacts (53 and 641, thu-s breaking the circuitwhich. was closed by engagement ot the contacts 68' and 69, but sincethe contacts 56 and 57 have previously been engaged the tloiv ot currentthrough the solenoid is not upward.

dien the last carrier disclliarges .trom the transmission tube thepressure in the latter increases slightly and the spring 35 immediatelyrestores the diaphra-gn'i 31 to its non nia-l position. This breaks thecircuit through the solenoid since the contacts 56 and 57 immediatelyseparate andas the solenoid is cle-energized the valve. L9- closes thuscutting oit atmospheric pressure from the chamber 15. As the main valveopened, the port 15a lifted above the upper surface ot the Wall 11 thusproviding a small passage between the chamber 15 and the chamber 141.Then leading to the passage 1()u was which is tapped in the chamber' 15to be expelled as the main val-ve comes to its fully closed position.

is the diaphragm 1Q moves downwardly the tinger elet engages the loiverend of the recess 41 in the member 39 and thus restores the member 39 toits. normal position permitting the contacts 63 and Getto re-engageWhile at the same time the cam bar @t6 moves downwardly and permits thecontacts 68 and (39 to separate. The parts are thus restored to` theirnormal position ready tor a subsequent operation.

I claim:

1. Power control apparatus torpneumatic dispatch systems comprising` amotor, electro-magnetic means tor controlling the operation of themotor, and a circuit closer and a circuit breaker both actuated by themotor.,

2. Power control apparatus tor a pneumatic dispatch systen'i having atransmission tube, said apparatus comprising a pneumatic motor having areciprocable element, acontrolling valve for the motor, anelectromagi'ietic device tor moving the valve, a normally open`electrical circuit including saidl electro-magnetic device'. a circuitcloser operable by the reciprocable element ot the motor for closingsaid circuit as the reciprocable element liegins its movement iuonedirection and a circuit breaker also operable by the recip-rocableele-ment ot the motor tor opening the circuit as the reciprocableelement approaches the limit ot its movement in said direction.`

3. Power control apparatus tor a pneumatic dispatch system havingatransmission tube. said apparatus comprising` a pneumatic motor havin-g`a reciprocaliile element, a normally closed controlling valve tor themotor, an electro-magnetic device :tor opening the valve. a norn'ial-lyopen electrical circuit including said electro-magnetic device, a.circuit closer operable by the reciprocable elementot the motor .torclosiimsaid circuit as the reciprocable element begins its movement inone direction and a circuit breaker also operable by the reciprocableeiement ot the motor tor opening the circuit as the reciprocable elementcompletes its said move-- ment, and means tor short circuiting` saidcircuit breaker whereby to maintain a Closed circuit througl'i theelectro-magnetic device so loue as a carri-.ef remains in the tube'.

4t. Power control apparatus tor a pneumatic dispatch system having atransmission tube and means tor creating a carrier propelling air dowtherein. said apparatus comprising a motor having a reciprocatingelenient. electro-maznetic means for controlling the operation ot themotor, an electrical circuit including' said electrai-magnetic device. anormally open switch device in circuit. a normally closed switch devicein said circuit. means actuable by the reciproci ile element ot themotor at it moves in one direction io close the nonmall;Y open switch,to hold it closed during the remainder ot' said movement oil thereciprocable element, and to open the normally closed switch, andindependent means 'tor maintaining' a clo l circuit througli theelectromagnet-ic dei ice so lone' as a carrier remains in thetransmission tube.

5, Power control apparatus tor a pneumatic dispatch system having atransmission tube and means for creatine; a carrier prolll) pelling airflow therein. said apparatus comprising` a motor having` a reciprocatingelement, elec lro-mag'netic means 'for controlling the operation ot themotor, an electrical circuit including' said electro-magnetic device, a`normally open switch device in said circuit. a normally closed snfitclidevice in said circuit, means a-ctuable by the reciprocable element ofthe motor as it moves in one direction to close the normally open switchand to keep it closed during the remainder of the movement of thereciprocating element, means operative by the motor for opening` thenormally closed switch as said reciprocatingelement nears the end ot itsstroke, and means Ytor maintaining a closed circuit through theelectro-magnetic device so long' as a carrier remains in thetransmission tube.

G. Power control apparatus of the class Vdescribed comprising' atransmission tube, a main valve. a reciprocable stem tor the valve, afluid motor for reciprocating the valve stem. a control valve for themotor, an electro-magnetic device for actuating` the control valve, anelectrical circuit including said electro-magnetic device. a normallyopen switch in the circuit. means carried by the main valve stein torclosing` said switch as the main valve begins to open and for holdingsaid switch closed while the main valve is open. a. normally closedswitch in the circuit.. means actuable by the valve stem as the valvenears its fully open position to open the latter switch, and meansindependent ot the main valve for maintaining a closed circuit throughthe electro-magnetic device so lon as a carrier remains in the tube.

7. Power control ap iarat-us of the class described comprising' a mainvalve. a reciprocabie stem fir the valve, a lluid motor 'forreciprocating the valve stem, a cont-rol valve for the motor, anelectro-magnetic device for actuating the control valve, an electricalcircuit including said electro-magnete device, a normally open switch inthe circuit, a normally closed switch in the circuit, cam meansact-uable by the main valve stem for closing,- the iirst switch as themain valve begins to open, other cam means for opening the other switch,lost motion connections between the latter cam means and the valve stem,and pressure actuated means independent of the main valve motor forsubsequently breaking the circuit through the electro-magnetic device.

S. Power control apparatus ot' the class described compi-isiuga mainvalve, a reciprocable stem it'or the valve, a fluid motor forreciprocating` the valve stem, a control valve for the motor, anelectromagnetic device for actuating the control valve, an electricalcircuit including said electro-magnetic device, a normally open switchin the circuit, a normally closed switch in the circuit, cam meansactuable by the main valve stem tor closing` the first switch as themain valve begins to open, a sliding bar parallel with the valve stem,said bar having a cam ele` ment for opening the second switch, said baralso having axially spaced stop elements, an arm carried by the mainvalve stem, one end ot the arm beingdisposed between said stop elements,and an auxiliary motor controlling a third switch in the circuit.

9. Power control apparatus ot' the class described comprising a mainvalve, a reciprocable stem 'tor the valve, a fluid motor torreciprocating the valve stem, a control valve .tor the motor, anelectro-magnetic device tor actuating the control valve, an electricalcircuit including said electro-magnetic device, a switch .in saidcircuit comprising parallel resilient support-s, normally separatedcontacts carried by the supports, a cam follower bloclr secured to oneot the supports, an elongate cam bar carried by the main valve stem andengageable with said cam follower as the valve begins to open whereby tomove the contacts into engagement and to hold them in engagementsubstantially so long as the main valve remains open, and meansindependent ot the main valve and its motor tor subsequently breakingthe circuit through the electromagnetic device.

10. Power control apparatus for a pneumatic dispatch system comprising amain valve, a motor i'or actuating it, an auxiliary valve controlling);the motor, electro-magnetic means 'tor movingthe auxiliary valve, and acircuit including' the windings ot the elec- 'tro-inagnetic means, saidcircuit comprising two branches, one branch bciun provided with anormally open switch and a nor mally closed switch and-tbe other having'a normally open switch, means actuated by tbe motor tor closing;l thenormally open switch and opening the normally closed switch of the firstbranch of the circuit, and independent means for closing the switch inthe second circuit before the normally closed switch is opened.

11. Power control apparatus for a pneumatic dispatch system having atransmission tube and means for creating carrier propelling air flowtherein, said apparatus comn prising a main Valve, a pneumatic foractuating it, an auxiliary Valve, a solenoid for moving the auxiliaryvalve, and an electrical circuit including the windings of the solenoid,said circuit having two branches, a normally open and a normally closedswitch in the first branch, a normally open switch in the second branch,means actuated by the pneumatic for successively closing the normallyopen switch and opening the normally closed switch in the first branchof theI circuit as the main valve moves from closed to fully openposition, and a fluid motor for closing, the switch in the other branchof the circuit and for keeping it closed so long as a carrier remains inthe transmission tube.

12. A power control apparatus comprising a pneumatic motor having achamber, a diaphragm forming one Wall of the chamber,

a port for admitting pressure i'iuid to the chamber, a Valve normallyclosing the port, and means actuable by the diaphragm for opening thevalve as the diaphragm mores inwardly to decrease the normal capacity ofthe chamber.

13. A power control apparatus comprising a pneumatic motor having adiaphragm, a port for admitting,1 pressure fluid to one side of thediaphragm, a Valve for closing` the port, and a pin carried by thediaphragm arranged to project through the port as the diaphragmapproaches its limit oll motion in one direction for opening the valve.

14C. A power control apparatus comprising,` a pneumatic motor having apressure chamber closed at one side by a movable diaphragm, a port inthe Wall of the chamber, a pivotally mounted valve cooperating' With theport, a counterweight normally closing` the valve, and a pin carried bythe diaphragm arranged to project through the port as the diaphragmapproaches one limit of its movement to open the valve.

Signed by me at Syracuse, New York this second day of December 1925.

i JAMES T. COVLEY.

